GIS and Index-Based Methods for Assessing the Human Health Risk and Characterizing the Groundwater Quality of a Coastal Aquifer

Abstract

The massive dune aquifer of Bouteldja is one of the most exploited aquifers in Algeria; as a result, its piezometric level has declined. Such pressure on the dune aquifer, in addition to its moderate-to-severe vulnerability to pollution, may lead to deterioration of groundwater quality. This study is intended to assess the quality of aquifer groundwater for drinking, irrigation and industrial purposes, and also to evaluate health risks. To this end, we analyzed data of 16 physicochemical parameters collected from 25 groundwater samples. Using the Durov diagram, principal component analysis (PCA), and Pearson's correlation matrix, we found that most major ions show similar origins related to ion exchange and the proximity of the sea. Our results showed that, overall, the groundwater intended for drinking purposes was of good or excellent quality over most the aquifer, where the majority of wells are located. However, the groundwater is mostly unsuitable for irrigation purposes according to the Kelly index (KI), percentage of sodium (Na %), magnesium hazard (MH), and irrigation water quality index (IWQI). Further, calculations of corrosivity ratios (CRs) indicated that the groundwater is unsuitable for industrial uses. Finally, a health risk assessment of iron heavy metal related to the hazard index (HI) for both ingestion and dermal exposure in children and adults showed negligible-to-low risk from iron exposure.